feat: add auto-update system with release checking, notification UI, and install-type-aware apply

- Abstract ReleaseProvider interface (Gitea impl, swappable for GitHub/GitLab)
- Background UpdateService with periodic checks, debounce, dismissed version persistence
- Install type detection (installer/portable/docker/dev) with platform-aware asset matching
- Download with progress events, silent NSIS reinstall, portable ZIP/tarball swap scripts
- Version badge pulse animation, dismissible banner with icon buttons, Settings > Updates tab
- Single source of truth: pyproject.toml version via importlib.metadata, CI stamps tag with sed
- API: GET/POST status, check, dismiss, apply, GET/PUT settings
- i18n: en, ru, zh (27+ keys each)

server/src/wled_controller/static/js/features/settings.ts

@@ -76,6 +76,11 @@ export function switchSettingsTab(tabId: string): void {
     if (tabId === 'appearance' && typeof window.renderAppearanceTab === 'function') {
         window.renderAppearanceTab();
     }
+    // Lazy-load update settings
+    if (tabId === 'updates' && typeof (window as any).loadUpdateSettings === 'function') {
+        (window as any).initUpdateSettingsPanel();
+        (window as any).loadUpdateSettings();
+    }
 }
 
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